Just returned from Hekou via the new road. Just 6 hours with a 30 minute rest stop. The distance is just shy of 300 km and the ticket prices are 150 RMB/CNY.

From the East Bus Station the bus will go to Shi Lin (Stone Forest), then Kai Yuan, then Mengzi and finally Hekou.

Wonderful!!!

i added a comment to this article that has a bit more info about the buses: www.gokunming.com/en/blog/item/2818/getting_away_sapa

I had heard the last gap in the Kunming-Hekou expressway was finally finished...the section from Suolongsi (north of Kaiyuan, where the Wenshan expressway branches off to the east) to Mengzi. But are the buses really taking the new expressway?

Also, even with the new expressway complete, this route has got to be more than 300 km. Before, with the gaps in the expressway, it was 410 km. The expressway will shave some of that distance off, but not a full 25% of it.

Like I posted above, I just returned from Hekou and the entire trip was less than 6 hours and the entire trip is via highway. Unless they purposely put wrong information on the highway signs, the distance is 300 km.

google has '412 km, 5 hours 33 mins' on the 'G8011开河高速'. the road appears to be highway all the way. not sure that's the correct route here but they say it's the shortest.

On Google Maps the stretch between Mengze (Honghe) and Pengpuzhen is still missing and by default they route you via Yuxi and Jianshui. The new road is a different one. First you go to Shillin and then pass Mile and Kaiyuan. Near Mengze you hit the old road to Vietnam again.
When you pass Mile you will see the exit sign S.Mile which always makes me smile. I don't know which joker made this sigh but there exist no N.Mile (And of course it should be Mile-S which it is in Chinese)

Since Google Maps still is not updated they cannot give you a total distance for this road but it should be around 400 Km. Take in mind that distance indications on Chinese highways are not always the distance to the actual town but the distance to the exit of that particular motorway for that town. At Shillin you enter a different motorway so the distance Hekou to Shillin might be 300 Km.

Note as well that Google maps has the administrative centre of Kunming Town in Chenggong as base when you type in "Kunming". This is nearly 30 Km away from what we regard as downtown Kunming.
(Another silly thing is that some time ago Dianchi Lake turned into Dianchi Pool and Yangzong Lake into Yangzong Sea. Luckily Fuxian Lake is still Fuxian Lake).

Wonderful how people prefer to get info from google rather than taking a bus ride. NO, the bus does not go near Mile nor does it go on any old roads.

OK good so all expressway now then.

Sounds like a trip I need to be making soon, wanted to go into Vietnam at some point so now I see this about simple expressway journey the trip is on!
I assume it was a worthwhile trip lol